(Invited) Important Recent Advancement of GaN Technology and MMICs for W-Band Applications

Monday, 2 October 2017: 10:40
Chesapeake A (Gaylord National Resort and Convention Center)
S. Chen, L. Witkowski, and X. Gu (Qorvo)
In this paper, we will present the in-development of Qorvo’s 90nm GaN technology imbedded within Qorvo’s existing 3-Metal-Interconnect (3MI) MMIC process flow, to make active and passive devices fully compatible with state-of-the-art GaN MMIC process, for V- and W-band MMIC High Power Amplifier (HPA) applications. By applying an advanced epitaxial material structure, dedicated T-gate configuration and process refinement, as well as 50-mm SiC substrate with Individual Source Via (ISV) FET construction, this technology demonstrates GaN FET devices with >145GHz Ft and >850mS/mm Gm, enables circuit designers to utilize this technology to pursue millimeter-wave market opportunities. Using this technology, a Technology characterization vehicle (TCV) MMICs using 5-stage 85GHz GaN power amplifiers have been demonstrated through circuit design, fabrication and measurements. This MMIC achieves greater than 38 dB small signal gain at 85GHz (8dB small signal gain per stage), and greater than 30 dB small signal gain over 72 – 90 GHz bandwidth. Further test results for both FET device and MMIC, including DC, small signal and power characteristics, will be reported in conference. This emerging GaN on SiC transistor technology is well suited for next generation millimeter-wave HPA, wideband and multi-function MMIC applications and beyond.

This work was funded by ONR (Program Manager: Dr. Paul A. Maki, ONR N00014-13-C-0071).